Attachment B - MTN Requirements and Objectives.pdf

ATTACHMENT B

MARS TELECOMMUNICATIONS NETWORK

OBJECTIVES AND REQUIREMENTS

DOCUMENT

MAY 14, 2026

RFP NUMBER: 80GSFC26R0011

CONTRACT NUMBER: TBD

MTN Objectives and Requirements MTN-402-REQ-0001, Rev C

Effective Date: May 14, 2026

Check https://ipdtdms.gsfc.nasa.gov/ to verify that this is the correct version prior to use.

National Aeronautics and Space Administration

Goddard Space Flight Center Greenbelt, Maryland

MTN-402-REQ-0001, Revision C

Mars Telecommunications Network

Mars Telecommunications Network (MTN)

Objectives and Requirements Document

GSFC MTN CMO

May 14, 2026

Released https://ipdtdms.gsfc.nasa.gov/

Change History Log

Revision Effective Date Description of Changes

- 3/19/2026 Initial Release

A 4/8/2026 Added MTN-REQ-049

Revised Ground Rule and Assumption 9 and 14

Added MTN-OBJ-005

Added MTN-REQ-050

Revised MTN-REQ-019

B 4/28/2026 Revised Sections 2.1 and 2.2 (MTN-PCB-0006)

Revised MTN-REQ-037, Added Appendix C (MTN-PCB-0008)

Revised Ground Rule and Assumption 9 (MTN-PCB-0004)

Revised Figures 1 and 2 (MTN-PCB-0004)

Added MTN-REQ-051 (MTN-PCB-0004)

Revised MTN-REQ-027 (MTN-PCB-0004)

Revised MTN-REQ-041 (MTN-PCB-0004)

Added MTN-REQ-052 (MTN-PCB-0004)

Revised MTN-REQ-024 (MTN-PCB-0004)

Added MTN-REQ-053 (MTN-PCB-0004)

Revised MTN-REQ-048 (MTN-PCB-0004)

Revised MTN-REQ-016 (MTN-PCB-0011)

Added MTN-REQ-054 (MTN-PCB-0009)

Updated Ground Rule and Assumption 8 (MTN-PCB-0010)

Revised MTN-REQ-006 (MTN-PCB-0010)

Added MTN-REQ-055 (MTN-PCB-0010)

Revised Appendix B (MTN-PCB-0012)

Updated Table B-6 EIRP and G/T Values (MTN-PCB-0012)

C 5/14/2026 Updated Appendix C SISE Equation

Table of TBDs/TBRs/TBSs

Action Item

No.

Location Summary Individual/

Organization

Actionee

TBD-02 MTN-

REQ-049

ICD to define scientific payload SMD

Table of Contents

1 INTRODUCTION

1.1 Purpose

1.2 Scope

1.3 Applicability

1.4 Stakeholders

2 REFERENCE AND APPLICABLE DOCUMENTS

2.1 Applicable Documents

2.2 Reference Documents

3 GOALS AND OBJECTIVES

4 GROUND RULES AND ASSUMPTIONS

5 SYSTEM OVERVIEW

6 MTN REQUIREMENTS

6.1 Project Requirements

6.2 Vehicle Requirements

6.3 DWE Link Requirements

6.4 Proximity Link Requirements

APPENDIX A: ABBREVIATIONS AND ACRONYMS

APPENDIX B: LINK BUDGET TEMPLATE

APPENDIX C: COMPUTING THE MTN SIGNAL-IN-SPACE-ERROR (SISE)

List of Tables

Table 1 Ground Rules and Assumptions Table 2 Science Payload Accommodation Table 3 Legacy Proximity Link Spectrum Table 4 Advanced Proximity Link spectrum

List of Figures

Figure 1 MTN Threshold Configuration Figure 2 MTN Goal Configuration

1 INTRODUCTION

Consistent with law, the National Aeronautics and Space Administration (NASA) is working toward a high-performance Mars telecommunications orbiter(s), capable of providing assets in and around Mars with robust, continuous communications with earth.

1.1 Purpose

The purpose of this Objectives and Requirements Document is to provide objectives and requirements for the Mars Telecommunications Network (MTN) Project.

The intent of these objectives and requirements is to support definition of the required “what” and to the maximum extent possible not define the “how”. However, since existing assets are already operating in and around Mars, legacy compatibility is required, and as such detailed specificity is provided in this document and associated applicable and reference documents. The longer-term vision is evolution of the existing Mars network to a higher performing system with extensibility to a 24/7 end state.

1.2 Scope

The scope of this requirements document includes orbiter(s), direct with earth (DWE), and

Proximity link related requirements. The document does not include specific launch vehicle-related requirements. This document also describes top-level objectives of the MTN orbiter(s).

1.3 Applicability

This objectives and requirements document is applicable to the MTN Project.

1.4 Stakeholders

The following are the key stakeholders for the MTN Project:

• Exploration Systems Development Mission Directorate (ESDMD)

• Space Operations Mission Directorate (SOMD)

• Strategy and Architecture Office (SAO)

• Science Mission Directorate (SMD)

• Space Communication and Navigation (SCaN) Program

• Moon to Mars (M2M) Program Office

2 REFERENCE AND APPLICABLE DOCUMENTS

2.1 Applicable Documents

Applicable documents are those documents that form a part of this document. These documents carry the same weight as if they were stated within the body of this document.

Document Number Document Title Revision

Architecture/Mission

NASA STD-871927 Implementing Planetary Protection Requirements for

Spaceflight

Proximity Links

211.0-B-6 CCSDS Prox-1 Space Link Protocol - Data Link Layer

211.2-B-2 CCSDS Prox-1 Space Link Protocol - Coding and

Synchronization Sublayer

211.1-B-4 CCSDS Prox-1 Space Link Protocol - Physical Layer

NASA NPR’s and Standards

NASA-STD-7009 Standard for Models and Simulations B

2.2 Reference Documents

Reference documents are those documents that, though not a part of this document, serve to clarify the intent and contents of this document.

Document Number Document Title Revision

Architecture/Mission

JPL D-106417 Mars Handbook 2022-2040 1.0

M2M Architecture Description Document C

NIST.FIPS.140-3 Federal Information Processing Standards Publication

Planetary Protection Handbook 2024

Direct with Earth Links

810-007 Deep Space Network (DSN) Mission Interface

Design Handbook

810-005 DSN Telecommunications Link Design Handbook

503.0-B-2 CCSDS Tracking Data Message

502.0-B-2 CCSDS Orbit Data Message

820-10 Deep Space Network Services Catalog

104-DSN 34-m BWG Stations Telecommunications Interfaces

875-0001 DSN Mission Service Interfaces, Policies, and

Practices (MSIPP)

H

820-10 Deep Space Network Services Catalog H

Proximity Links

MRN Participation Guide

MRN Participation Guide Technical Support Package

734.20-O-1 CCSDS Bundle Protocol Specification

734.1-B-1 CCSDS Licklider Transmission Protocol (LTP)

141.0-B-1 CCSDS Optical Communications Physical Layer

142.0-B-1 CCSDS Optical Communications Coding and

Synchronization

732.0-B-4 CCSDS AOS Space Data Link Protocol

732.1-B-3 CCSDS Unified Space Data Link Protocol

REC 22-1 Frequency Assignment Guidelines for

Communications in the Mars Region

MTN-SYS-DESC-0001 Adaptive Data Rates (ADR) on Mars Ultra-High

Frequency (UHF) Relay

NASA NPR’s and Standards

NPR 7123.001 NASA System Engineering Processes and

Requirements

D

Lunanet Interoperability Specification 5

FIPS 197 Advanced Encryption Standard (AES)

NPR 8705.4 Risk Classification for NASA Payloads A

NASA/SP-20240016475 NASA Planetary Protection Handbook

NASA-STD-8719.14 Process for Limiting Orbital Debris C

NPR 8715.6 NASA Procedural Requirements for Limiting Orbital

Debris and Evaluating the Meteoroid and Orbital

Debris Environments

B

3 GOALS AND OBJECTIVES

The top-level objectives of the MTN project are identified as:

MTN-OBJ-001

Provide communication and data exchange between assets in the Mars vicinity, the Mars surface, and Earth anticipated to operate at Mars through 2035.

MTN-OBJ-002

Provide Doppler, range, and time transfer to support positioning, navigation, and timing for assets anticipated to operate at Mars through 2035.

MTN-OBJ-003

Provide communication services to existing operational missions.

MTN-OBJ-004

Provide communications, Doppler, range, and time transfer services to the Entry, Descent, and Landing (EDL) demonstration missions anticipated to operate at Mars through 2035.

MTN-OBJ-005

Provide spacecraft bus integration, accommodation, and communication services to a science payload provided by NASA.

4 GROUND RULES AND ASSUMPTIONS

The ground rules and assumptions are identified and defined in the following table:

ID Ground Rule / Assumption

1 MTN will not require, nor does it preclude surface-to-surface relay communications for 2035 uses.

2 MTN will not require, nor does it preclude orbiter crosslink capability.

However, 24/7 end state extensibility is envisioned in the future.

3 The MTN will be compatible with the DSN communication links from deep space to Earth.

4 The MTN communication links from orbiter(s) to DSN will require ground compatibility testing with DSN, prior to launch. (Test assets such as DSN

CTT-22, MIL-71 and DTF-21 may be available subject to negotiation with

NASA)

5 The MTN contractor will deliver to NASA an MTN portable test unit for

Proximity link compatibility testing for future mission users for all Proximity links.

6 MTN will require adaptive data rates on the Proximity link, consistent with existing capability.

7 MTN will not require optical communications for DWE link, but could be considered as part of a contractor’s proposal

8 MTN will require low-rate X-band and higher rate Ka-band DWE links.

9 MTN will require S-band, Ku-band or K/Ka-band Advanced Proximity links for higher rate missions

10 MTN will require UHF Legacy Proximity links.

11 NASA is procuring an MTN system via Fixed Price Contract (FFP), and scope includes ground and flight hardware delivery to NASA. Launch and future operations will be handled via contract options.

12 Launch vehicle interface will be proposed and managed by the contractor.

There are no specific requirements included for a particular launch vehicle.

13 MTN will require scheduling functionality and associated interfaces for both

DWE and Proximity links

14 Hosting a SMD science payload is on a do-no-harm basis, and schedule risk is critically important.

Table 1 Ground Rules and Assumptions

5 SYSTEM OVERVIEW

This document implements a nomenclature of “threshold” and “goal” requirements. The

“threshold” requirements define the minimum performance and functional requirements necessary to achieve an acceptable system. The “goal” requirements define stretch targets that are desired by project stakeholders that represent meaningful improvement over the minimum viable system.

Figure 1 MTN Threshold Configuration

Figure 2 MTN Goal Configuration

6 MTN REQUIREMENTS

6.1 Project Requirements

MTN-REQ-001 Operational Lifetime

Threshold Requirement: MTN shall provide communications and Position, Navigation, and

Timing (PNT) services for a minimum operational lifetime of 5 Earth years, beginning at operational readiness.

Goal Requirement: N/A

Rationale: A 5-year operational lifetime ensures the MTN architecture can provide stable relay services across multiple Mars missions and demonstrations beginning at operational readiness.

For the purposes of this requirement, operational readiness is defined as post-commissioning and ready to provide full operational capability. (Ref. Moon-to-Mars Architecture Description

Document Rev. C)

Verification Method: Analysis

Traceability: MTN-OBJ-001, MTN-OBJ-002, MTN-OBJ-003, MTN-OBJ-004

MTN-REQ-002 Proximity Link Continuity of Service

Threshold Requirement: MTN shall provide Proximity Link radiometric and communications services to current and in development Mars surface assets.

Rationale: Integrated communications and radiometric services are required to support commanding, telemetry, and precision navigation for existing and in-development Mars surface assets at UHF using the Proximity-1 Space Link Protocol (Ref. CCSDS 211.2-B-2, “Proximity-1

Space Link Protocol—Coding and Synchronization Sublayer”; CCSDS 211.1-B-4, “Proximity-1

Space Link Protocol - Physical Layer”; CCSDS 211.0-B-6, “Proximity-1 Space Link Protocol -

Data Link Layer”) Note there are slight differences between NASA and European Space

Agency (ESA) assets that must be accommodated and there are also slight differences with the protocol specification from both types of assets.

Verification Method: Test

Traceability: MTN-OBJ-001, MTN-OBJ-002, MTN-OBJ-003

MTN-REQ-003 Non-Real-Time Store-and-Forward

Threshold Requirement: MTN shall provide store-and-forward capability for DWE and

Proximity communications.

Rationale: Providing non-real-time, store-and-forward enables reliable data delivery despite long delays, intermittent visibility, and periodic loss of line-of-sight between surface, orbital, and

Earth segments ensuring continuous mission communications in Mars orbital geometries without requiring real-time connectivity.

Traceability: MTN-OBJ-001, MTN-OBJ-003, MTN-OBJ-004

MTN-REQ-004 Concurrent Service Provision

Threshold Requirement: MTN shall support concurrent full duplex operation of communications relay DWE, Proximity communications, and associated services.

Rationale: Concurrent, non-interfering operation of communications relay, semi-real-time delivery, DTN networking, navigation, timing, and messaging is required to support overlapping mission activities without degrading critical services. This capability ensures predictable performance under peak load, protects time-critical functions, and enables MTN to operate as reliable, multi-mission infrastructure consistent with SCaN architecture and NASA risk-informed systems engineering practices (CCSDS BPv7, NPR 7123.1, NPR 8705.5).

MTN-REQ-005 Hardware Delivery Date

Threshold Requirement: The contractor shall deliver completed ground and flight systems to

NASA including completion of all associated reviews and inspections by December 31, 2028.

Rationale: Consistent with Pub. L. 119-21, delivery by end of CY2028 ensures continuity of critical relay services and prevents a communications gap as existing Mars orbiters age.

Verification Method: Inspection

MTN-REQ-006 DWE Service

Threshold Requirement: Mars Telecommunications Network shall provide all DWE forward & return links during transit to Mars and in Mars operational orbit, excluding solar conjunction and occultations.

Rationale: The DWE link returns user science data to Earth and is needed for MTN operations at

Mars. The transit phase from Earth to Mars is an opportune time to check out the high rate DWE return link.

Traceability: MTN-OBJ-001, MTN-OBJ-005

MTN-REQ-007 Mission Environment

Threshold Requirement: MTN shall operate as specified herein when exposed to all expected environments through all expected mission phases.

Rationale: The MTN, in addition to on-orbit lifecycle, will be exposed to all relevant operational environments through deployment into orbit including but not limited to orbital insertion, time-light delays from ground command preventing timely intervention and potential intermittent loss of communication and command. (Ref. Mars Handbook 2022-2040 Release 1.0)

MTN-REQ-008 Solar Conjunction

Threshold Requirement: The MTN DWE connections shall operate at Sun-Earth-probe angles at

3°and greater.

Goal Requirement: The MTN DWE connections shall operate at Sun-Earth-probe angles at

2°and greater.

Rationale: The Earth-Mars solar conjunction will prevent communications between Earth and

Mars for the duration the time of the actual line-of-sight blockage. Designing communication links to operate within 3° of the blockage will increase the availability of the links by incorporating mitigation techniques and link margin to optimize communications in the presence of solar adverse effects on the respective receivers. Operational constraints may be imposed to mitigate the potential of corrupted commands sent to the spacecraft. For this requirement, threshold values reflect expected performance of X-Band transmission.

MTN-REQ-009 Ground Commanded Prioritization

Threshold Requirement: The MTN shall provide the capability for data prioritization.

Rationale: The MTN will service multiple end users. Therefore, it is necessary to provide a means of prioritizing data to facilitate link scheduling. This prioritization scheme is controlled by ground personnel and can be specified prior to and after the network services are rendered.

MTN-REQ-010 Scheduling Functionality

Threshold Requirement: The MTN shall implement a means for user scheduling and providing associated interfaces for both DWE and Proximity links.

Rationale: The MTN will service multiple end users. Therefore, it is necessary to provide for scheduling ground station assets and coordinate user scheduling of proximity interfaces along with the associated interfaces for user data.

Verification Method: Demonstration

MTN-REQ-011 Link Performance

Threshold Requirement: The MTN shall meet end-to-end performance for all communication links with ≥3 dB margin.

Rationale: Meeting end-to-end performance at maximum range with at least 3 dB margin ensures reliable communications under nominal conditions. The ≥ 3 dB link margin requirement provides explicit robustness against link modeling uncertainty, hardware performance drift, pointing error, aging of RF components, and unmodeled environmental or propagation effects.

This aligns with NASA systems engineering guidance (e.g., NPR 7123.1 and NASA-STD-7009) to include appropriate performance margin for model-based predictions and long-life space assets, reducing the risk of link outages, increased retransmissions, or permanent loss of service.

Communication links to be assessed using provided link budget template (Appendix B).

MTN-REQ-012 Bit Error rate

Threshold Requirement: All MTN communication links shall have a bit error rate of 10-7 or better.

Rationale: This value is aligned with NASA best practice and ensures for accurate decryption of command link. Communication links to be assessed using provided link budget template

(Appendix B).

MTN-REQ-049 Scientific Payload Considerations

Threshold Requirement: MTN shall accommodate a NASA science payload per [TBD-02] conforming to the interface and not-to-exceed envelope depicted in Table 2.

Criteria Value Units

Basic Mass 20 kg

Dimensions 55x55x45 cm x cm x cm

Nominal Power 60 W

Peak Power 60 W

Power Interface Port 28V

Communication Interface Wired

Data Comm Port RS-422, Ethernet

Max Instantaneous Data Rate 25 kbps

Daily Data Volume 200-1000 Mb

Requires Thermal Isolation No

Shock Load Limit GEVS

Table 2 Science Payload Accommodation

Rationale: MTN stakeholders anticipate the inclusion of scientific payloads. All payloads will be negotiated with the NASA team and will not impact MTN schedule requirements. While certain attributes of Table 2 imply a payload functioning as part of the MTN flight system, a deployable

CubeSat that fits within the mass and volume envelope of Table 2 is also under consideration.

Traceability: MTN-OBJ-005

MTN-REQ-055 Telemetry During Critical Events

Threshold Requirement: MTN shall provide DWE X-Band real-time or recorded telemetry capability for all flight phases and critical events (i.e. launch & ascent, separation, transit, and insertion).

Goal Requirement: MTN shall provide DWE X-Band real-time capability for all flight phases and critical events (i.e. launch & ascent, separation, transit, and insertion).

Rationale: To the greatest extent practicable, all critical events should have either real-time or stored (recorded) telemetry for post-event assessment. There is no requirement for interleaving spacecraft and launch vehicle telemetry although it is not precluded. Note that the MTN project will need to assess any waivers to NASA’s review criteria for launch and critical events, such as real-time telemetry during spacecraft separation and initial stabilization. (Ref. NPR 8705.4)

Traceability: MTN-OBJ-001

6.2 Vehicle Requirements

MTN-REQ-013 Operational Readiness

Threshold Requirement: MTN shall achieve full operational readiness at Mars no later than end of calendar year 2030.

Goal Requirement: MTN shall achieve full operational readiness at Mars no later than end of calendar year 2029.

Rationale: Achieving MTN operational readiness by the end of 2030 ensures continuity of critical relay services and prevents a communications gap as existing Mars orbiters age.

Aligning MTN’s operational readiness with the 2028–2029 Mars launch opportunity reduces risk to dependent surface and orbital missions and supports stable programmatic planning and sustained Mars exploration. This is consistent with Pub. L. 119-21, to deliver the MTN orbiter(s) to NASA by end of CY2028. For the purposes of this requirement, operational readiness is defined as post-commissioning and ready to provide full operational capability.

MTN-REQ-014 Non-Volatile Store-and-Forward Memory (DWE)

Threshold Requirement: MTN shall provide at least 1.0 Tbyte of non-volatile store and forward capability for the DWE link.

Rationale: Providing non-real-time data, store-and-forward capability enables reliable data delivery despite long delays, intermittent visibility, and periodic loss of line-of-sight between surface, orbital, and Earth segments ensuring reliable mission communications in Mars orbital geometries without requiring real-time connectivity. This value reflects an assumed average data-rate of 7 Mbps over an 8-hour pass per day for 2 days with a factor of 10 margin.

MTN-REQ-015 Non-Volatile Store-and-Forward Memory (Proximity)

Threshold Requirement: MTN shall provide at least 0.5 Tbyte of non-volatile store and forward capability for the Proximity link(s).

Rationale: Providing non-real-time data, store-and-forward capability enables reliable data delivery despite long delays, intermittent visibility, and periodic loss of line-of-sight between surface, orbital, and Earth segments ensuring reliable mission communications in Mars orbital geometries without requiring real-time connectivity.

MTN-REQ-016 Cybersecurity & Command Protection

Threshold Requirement: MTN shall utilize cybersecurity and command link encryption practices consistent with industry best practices, such as AES-256 utilizing a 256-bit cryptographic Traffic

Encryption Key (TEK) per NIST FIPS PUB 197 certified for FIPS-140-3 level 1 or equivalent.

Rationale: NASA-approved security is required to protect MTN commanding, data integrity, and authentication against unauthorized access and data compromise. It is encouraged to implement existing industry practices where appropriate.

MTN-REQ-017 Planetary Protection Guidelines

Threshold Requirement: MTN shall follow all Agency applicable Planetary Protection guidelines

(NPD 1000.3, NASA/SP-20240016475, NASA-STD-8719.27).

Rationale: As a Class 3 Mars Orbital mission per NPR 8719.27, MTN is required to provide

NASA with access to the spacecraft, facilities, and documentation to accommodate planned independent verification and assurance activities, development of risk mitigation protocols, and any anomaly investigations throughout the project life cycle to achieve compliance with applicable Agency planetary protection requirements.

MTN-REQ-018 Orbital Debris

Threshold Requirement: MTN shall follow all Agency applicable Mars Orbital Debris requirements (NASA-STD-8719.14, NPR 8715.6).

Rationale: MTN is required to demonstrate compliance with NASA Mars Orbital debris reduction requirements NASA-STD-8719.14 and NPR 8715.6 to limit debris generation, spacecraft vulnerability, post-mission lifetime, and maximize entry safety.

MTN-REQ-019 Maximum Interlink Data Transfer Rates

Threshold Requirement: The MTN shall have the onboard capability to support continuous, minimal latency, and full rate data transfer between the Direct with Earth links and the Proximity links, and between different Proximity links.

Rationale: The MTN will be capable of supporting high-rate communications on both the DWE and Proximity links. This requirement ensures that there are no hardware bottlenecks in moving data from one interface to another or in internal processing of the MTN.

MTN-REQ-020 Deleted

MTN-REQ-040 Radio Reprogramming

Threshold Requirement: MTN shall support in-flight reprogramming of any software and firmware used either for Proximity link or DWE link protocol handling or digital signal processing.

Rationale: As a long-term relay service provider with unknown future users, it is important for

MTN to support updates to the radio software and Field Programable Gate Array (FPGA)

Hardware Description Language (HDL) used for relay services, which can address both critical compatibility issues and service improvements. This has been demonstrated to be of great value with the existing Mars relay network, with post-launch upgrades significantly improving relay performance.

Verification Method: Demonstration

MTN-REQ-042 Autonomous Navigation

Threshold Requirement: N/A

Goal Requirement: MTN shall estimate its navigation state onboard without utilization of Earth-based radiometric tracking.

Rationale: MTN is chartered to support autonomous operations and onboard processing.

Updating the navigation state onboard is key to enabling more autonomous operations at Mars, which will be critical to systems at Mars operating more independently from Earth.

Traceability: N/A

MTN-REQ-051 MTN Spectrum Allocations

Threshold Requirement: The MTN Offeror shall provide NASA the analysis and data required for spectrum application and authorization process for Legacy Proximity, Advanced Proximity, and DWE links and all spectrum allocation shall comply with U.S. Table of Frequency

Allocations and National Telecommunications and Information Administration (NTIA) and/or

NASA processes for frequency allocations and channel assignments.

Rationale: The selection of frequency supports operation and interoperability from different service providers, and must comply with spectrum allocation procedures, assignments available to NASA for operations, and meet internationally coordinated spectrum allocations, where applicable. Note that the frequencies currently in SFCG 22-1R4 are recommendations only and do not guarantee allocation for Mars applications. Bandwidth use is expected to be spectrum-efficient within channel assignments in the specified bands and coordinated with NASA.

Verification Method: Inspection, Analysis

MTN-REQ-054 Link Protocols

Threshold Requirement: N/A

Goal Requirement: Non-proprietary communication waveforms and protocols shall be used for all communications links.

Rationale: Use of non-proprietary communication protocols ensures future Mars Telecom

Network assets can be interoperable. Internationally accepted standards, such as the

Consultative Committee for Space Data Systems (CCSDS) are preferred. The Optical

Communications High Photon Efficiency standard has been approved by space agencies for deep space optical communications links, such as those from Mars.

6.3 DWE Link Requirements

MTN-REQ-021 Deleted

MTN-REQ-022 DWE Link 2-Way Coherent Ranging & Doppler

Threshold Requirement: MTN shall provide 2-way coherent ranging and 2-way coherent

Doppler on the DWE links with a range precision 1 m and Doppler precision of 0.1 mm/s (1-sigma) at a 60 second count time.

Rationale: Two-way coherent ranging and Doppler provide the highest-accuracy range and velocity measurements needed for precise navigation and orbit determination. These capabilities are essential for high-consequence operations and reduce mission risk by enabling stable, validated navigation solutions. Precision replicates current accuracy capability of existing systems.

Traceability: MTN-OBJ-002

MTN-REQ-023 DWE Link Communication Availability

Threshold Requirement: MTN hardware and software shall provide an average annual DWE link availability of ≥95%, exclusive of the Earth ground segment, channel propagation effects, and

Goal Requirement: MTN hardware and software shall provide an average annual DWE link availability of ≥99%, exclusive of the Earth ground segment, channel propagation effects, and

Rationale: A service availability of at least 95% ensures MTN provides reliable, predictable support for mission-critical communications and navigation. This requirement drives resilient system design and reduces operational risk for sustained Mars exploration. This is achieved through a combination of low and high rate DWE communications. This requirement is on the

MTN portion of the link and not the availability of the Earth side of the link or line of sight obstructions.

MTN-REQ-024 X-band DWE Link at Max Range

Threshold Requirement: MTN shall support Deep Space X-band DWE link data rates up to at least 0.1 Mbps Forward (DSN to MTN), and up to at least 0.5 Mbps Return (MTN to DSN) at

Mars–Earth maximum range (~400Mkm), using a single 34m BWG DSN antenna.

Goal Requirement: MTN shall support Deep Space X-band DWE link data rates up to at least 1.0

Mbps Forward (DSN to MTN) and up to at least 1.0 Mbps Return (MTN to DSN) at Mars–Earth maximum range (~400Mkm), using a single 34m BWG DSN antenna.

Rationale: Specifying minimum DWE data rates at Mars–Earth maximum range ensures MTN can provide commanding and high-volume data return under worst-case link conditions.

Specified rates support efficient, high-throughput operations consistent with DSN services. The statement “up to at least” provides for variable data rates below the stated rate, but also not preclude rates above the stated rate, consistent with MTN-REQ-034. Designing to these thresholds drives DSN compatibility and supports resilient, campaign-level MTN infrastructure in accordance with DSN interface guidance, SCaN architectural direction, and NASA systems engineering practices (820-100-H DSN Services Catalog; NPR 7123.1). RF communication links to be assessed using provided link budget template (Appendix B).

MTN-REQ-053 X-band DWE Link Variable Range

Threshold Requirement: MTN shall support Deep Space DWE Links at X-band with data rates up to at least 3.1 Mbps Return (MTN to DSN) and up to at least 3.1 Mbps Forward (DSN to

MTN) at Earth-MTN ranges where sufficient link margin exists to meet MTN-REQ-012, using a single 34m BWG DSN antenna.

Rationale: Specifying variable DWE data rates ensures that the MTN can maximize high-data volume return over the entire Earth-Mars synodic period, taking advantage of variations in range between the two planets. The statement “up to at least” provides for variable data rates below the stated rate, but also not preclude rates above the stated rate, consistent with MTN-REQ-034.

Specified rates support efficient, throughput operations consistent with DSN services, and with encoding options, remain within the 8 MHz X-band DWE bandwidth allocation. Designing to these thresholds drives DSN compatibility and supports resilient, campaign-level MTN infrastructure in accordance with DSN interface guidance, SCaN architectural direction, and

NASA systems engineering practices (820-100-H DSN Services Catalog; NPR 7123.1). RF communication links to be assessed using provided link budget template (Appendix B).

MTN-REQ-041 High-Rate DWE Link at Max Range

Threshold Requirement: MTN shall support Deep Space High-Rate DWE Links at Ka-band with data rates up to at least 3.0 Mbps Return (MTN to DSN) at Mars–Earth maximum range

(~400Mkm), using a single 34m BWG DSN antenna.

Goal Requirement: MTN shall support Deep Space High-Rate DWE Link data rates up to at least

2.0 Mbps Forward (Earth-to-MTN) and up to at least 5.0 Mbps Return (MTN to Earth) at Mars–

Earth maximum range (~400Mkm). Where DSN support is assumed, data rates for forward and return links shall be met using a single 34m BWG DSN antenna.

Rationale: Specifying minimum DWE data rates at Mars–Earth maximum range ensures MTN can provide commanding and high-volume data return under worst-case link conditions.

Specified rates support efficient, high-throughput operations consistent with DSN services.

Designing to these thresholds drives DSN compatibility and supports resilient, campaign-level

MTN infrastructure in accordance with DSN interface guidance (820-100-H DSN Services

Catalog), SCaN architectural direction, and NASA systems engineering practices (NPR 7123.1;

MTN Handbook). The statement “up to at least” provides for variable data rates below the stated rate, but also not preclude rates above the stated rate, consistent with MTN-REQ-034. The Goal requirement in addition to adding the forward link, increases the return data rate, while allowing consideration of additional frequency bands of operation for the DWE link. RF communication links to be assessed using provided link budget template (Appendix B).

MTN-REQ-052 High-Rate DWE Link Variable Range

Threshold Requirement: MTN shall support Deep Space High-Rate DWE Links at Ka-band with data rates up to 50.0 Mbps Return (MTN to DSN) at Mars–Earth range where sufficient link margin exists to meet MTN-REQ-012, using a single 34m BWG DSN antenna.

Goal Requirement: MTN shall support Deep Space High-Rate DWE Link data rates up to at least

40 Mbps Forward (Earth-to-MTN) and up to at least 150 Mbps Return (MTN to Earth) at Mars–

Earth range where sufficient link margin exists to meet MTN-REQ-012. Where DSN support is assumed, data rates for forward and return links shall be met using a single 34m BWG DSN antenna.

Rationale: Specifying maximum DWE data rates ensures that the MTN can maximize high-data volume return over the entire Earth-Mars synodic period, taking advantage of variations in range between the two planets. Designing to these thresholds meets DSN compatibility and supports resilient, campaign-level MTN infrastructure in accordance with DSN interface guidance, SCaN architectural direction, and NASA systems engineering practices (820-100-H DSN Services

Catalog; NPR 7123.1). The statement “up to at least” provides for variable data rates below the stated rate, but also not preclude rates above the stated rate, consistent with MTN-REQ-034. The

Goal requirement in addition to adding the forward link, increases the return data rate, while allowing consideration of additional frequency bands of operation for the DWE link. RF communication links to be assessed using provided link budget template (Appendix B).

MTN-REQ-025 DWE Link / Deep Space Network (DSN) Compatibility

Threshold Requirement: MTN shall be compatible with DSN per DSN Mission Interface Design

Handbook (810-007) and DSN Telecommunications Link Design Handbook (810-005).

Goal Requirement: MTN shall be compatible with DSN per DSN Mission Interface Design

Handbook (810-007), DSN Telecommunications Link Design Handbook (810-005) and provide functionality to support Multiple Users per Aperture (MUPA)

Rationale: Compatibility with the Deep Space Network (DSN) ensures that MTN can use

NASA’s primary interplanetary communications infrastructure without custom interfaces or redesign. The DSN Mission Interface Design Handbook (810-007) is the authoritative source for all flight projects using the DSN and provides required interface guidance, service capabilities, and customer requirements. Designing to 810-007 reduces technical and schedule risk, ensures interoperable communications and tracking services, and enables clear verification against an approved DSN baseline. Multiple Users per Aperture (MUPA) is a desired functionality which will require the ability to acquire an uplink signal when multiple spacecraft are using a single aperture.

MTN-REQ-026 DWE Link / CCSDS Protocol Compatibility

Threshold Requirement: Threshold Requirement: MTN shall implement the CCSDS Bundle

Protocol version 7 (BPv7) (CCSDS 734.20-O-1) for data transfer in the DWE link.

Goal Requirement: MTN shall implement the CCSDS Licklider Transmission Protocol (LTP)

(CCSDS 734.1-B-1), for reliable data transfer in the DWE link.

Rationale: Implementing CCSDS BPv7–compliant interfaces ensures MTN can reliably interoperate with NASA, international, and commercial assets using standardized communications protocols.

MTN-REQ-044 DWE Return Link Selectable Data Rates

Threshold Requirement: The MTN DWE Return Link shall support a series of selectable data rates to efficiently utilize the available link margin across the variable Mars-Earth range.

Goal Requirement: N/A.

Rationale: As the distance between Mars and Earth varies from approximately 55 million to 400 million kilometers over their respective orbits, the associated change in free‑space path loss produces substantial variation in signal strength at Earth. When the planets are nearer, the reduced path loss enables higher data rates and yet still maintains required link margins.

Adapting data rates throughout the orbital cycle ensures efficient and robust communication across all DWE frequencies.

MTN-REQ-045 DWE Forward Link Selectable Data Rates

Threshold Requirement: The MTN DWE Forward Link shall support a series of selectable data rates to efficiently utilize the available link margin across the variable Mars-Earth range.

Rationale: As the distance between Mars and Earth varies from approximately 55 million to 400 million kilometers over their respective orbits, the associated change in free‑space path loss produces substantial variation in signal strength at Earth. When the planets are nearer, the reduced path loss enables higher data rates and yet still maintains required link margins.

Adapting data rates throughout the orbital cycle ensures efficient and robust communication across all DWE frequencies.

MTN-REQ-047 DWE Link Channel Assignment

Threshold Requirement: The MTN DWE links shall operate on the frequency channels/bandwidths assigned by NASA.

Rationale: The MTN does not expect bandwidth for X-band to exceed 10MHz and Ka-band to exceed 100MHz. Frequency authorization for each communication link is needed in accordance with NPD 2570.5E NASA RF Spectrum Management and National Telecommunications and

NTIA Manual of Regulations & Procedures for Federal Radio Frequency Management (May

2013 Edition, May 2014 Revisions) Chapter 10.

6.4 Proximity Link Requirements

MTN-REQ-027 Proximity Link Orbital Coverage

Threshold Requirement: The MTN shall provide service to surface assets and orbital assets up to an altitude of 500 km.

Rationale: This requirement serves to set the minimum service volume (3D volume space) for orbital users of the MTN.

MTN-REQ-028 Proximity Link Surface Coverage

Threshold Requirement: MTN shall provide services for all latitudes up to ±50° from the Martian geographical equator, and for all longitudes.

Rationale: Near-global coverage ensures the MTN system can provide reliable services for all latitudes up to +/-50 degrees from the Martian geographical equator, and for all longitudes, with only limited polar exclusions. This capability supports current NASA missions and reduces operational risk by providing consistent, predictable relay access aligned with sustained, campaign-level Mars exploration objectives. If implementing a multi-spacecraft system, this requirement applies to the network, not each unit. Coverage should optimize number of passes and pass duration to extent possible within the design constraints. For reference, current surface assets receive 2 passes per sol with current relay systems.

MTN-REQ-029 Proximity Link Time Transfer Data Correlation

Threshold Requirement: MTN shall provide radiometric time-transfer services to surface and orbital assets where the time correlation accuracy of in-situ time transfer data is traceable to

Coordinated Universal Time (UTC) to within ≤ 1 millisecond error (3-sigma) at the user interface.

Goal Requirement: The MTN shall provide radiometric time-transfer services to surface and orbital assets where the time correlation accuracy of in-situ time transfer data is traceable to UTC to within ≤ 1 microsecond error (3-sigma) at the user interface.

Rationale: Accurate radiometric time-transfer provides timing data needed for precise positioning, navigation, and timing at Mars. This capability reduces navigation errors, supports time-critical operations, and enables reliable, interoperable PNT services for surface and orbital assets. This requirement is not intended for specifying formation of a Mars time scale (at least at this time) that is maintained to UTC or imply that Mars timing should utilize leap seconds;

however, it is intended to specify the capability of the MTN to correlate its own clocks and time relative to UTC (the civilian timescale we use and ‘tied’ to Earth Terrestrial Time (TT)) and then be able to transfer that time correlation information to user clocks so that they can relate their time to Earth-based times. Note that this will require monitoring and tracking the physical drift of MTN’s clocks and associated frequencies as well as the proper time/frequency expected in the

Mars local relativistic environment (and how it relates to terrestrial and solar system barycentric relativistic environments).

Traceability: MTN-OBJ-002, MTN-OBJ-003, MTN-OBJ-004

MTN-REQ-030 Proximity Link Communication Availability

Threshold Requirement: MTN shall provide an average annual Proximity Link service availability ≥98% during the Proximity Communications windows.

Goal Requirement: MTN shall provide an average annual Proximity Link service availability

≥99% during the Proximity Communications windows.

Rationale: A service availability of at least 98% ensures MTN provides reliable, predictable support for mission-critical communications and navigation. This requirement drives resilient system design and reduces operational risk for sustained Mars exploration.

MTN-REQ-031 UHF Proximity Link Data Rates

Threshold Requirement: MTN shall support UHF Proximity Link communications services for surface and orbital assets at Mars with per-user data rates up to at least 2 Mbps under nominal conditions at zenith, with the zenith distance defined to be the closest approach radial distance of

MTN to the surface or orbital asset.

Goal Requirement: MTN shall support UHF Proximity Link communications services for surface and orbital assets at Mars with per-user data rates up to at least 8 Mbps under nominal proximity rate conditions at zenith, with the zenith distance defined to be the closest approach radial distance of MTN to the surface or orbital asset.

Rationale: Mars surface and orbital missions depend on Proximity relay communications to return science, engineering, and health data when direct-to-Earth links are unavailable. Existing

NASA Mars missions and relay orbiters establish a proven operational baseline for UHF

Proximity return-link throughput that the MTN seeks to build upon. Specifying minimum

Proximity return-link data rates ensures continuity and interoperability with deployed Mars assets while preserving flexibility in Proximity relay architecture and implementation.

Typically, the lower bound on the communications distance (the zenith distance in the requirement) will have a lower bound equal to the minimal orbital altitude of the Mars Relay

Network (MRN). Communication links to be assessed using provided link budget template

(Appendix B).

MTN-REQ-032 Advanced Proximity Link Data Rates

Threshold Requirement: MTN shall support Advanced (non-UHF) Proximity Link communications for surface and orbital assets at Mars with per-user data rates up to at least 25

Mbps under nominal Proximity rate conditions at zenith, with the zenith distance defined to be the closest approach radial distance of MTN to the surface or orbital asset.

Goal Requirement: MTN shall support Advanced (non-UHF) Proximity Link communications for surface and orbital assets at Mars with per-user data rates up to at least 100 Mbps under nominal Proximity rate conditions at zenith, with the zenith distance defined to be the closest approach radial distance of MTN to the surface or orbital asset.

Rationale: Mars surface and orbital missions depend on Proximity relay communications to return science, engineering, and health data when direct-to-Earth links are unavailable.

Advanced Proximity link data rates are derived from stakeholder input and anticipated needs within the MNT operational lifetime. Typically, the lower bound on the communications distance (the zenith distance in the requirement) will have a lower bound equal to the minimal orbital altitude of the MRN. Communication links to be assessed using provided link budget template (Appendix B).

MTN-REQ-033 Simultaneous Proximity Links

Threshold Requirement: MTN shall simultaneously support ≥ 2 simultaneous concurrent full-duplex legacy links and ≥ 1 advanced Proximity links within the MTN Proximity antenna fields of view.

Rationale: Supporting at least two concurrent full-duplex legacy links and at least one advanced proximity link (for a total of at least 3 links) enables MTN to provide simultaneous two-way communications for multiple surface and orbital users, reducing scheduling conflicts and supporting time-critical operations. This capability ensures MTN can function as shared, resilient campaign infrastructure with acceptable operational risk (NASA-HDBK-1002).

MTN-REQ-034 Adaptive Data Rates

Threshold Requirement: The MTN Proximity link system shall support adaptive data rates from surface and orbital assets.

Rationale: Adaptive Proximity links will achieve significant improvement in throughput capacity by using available link margin. Requires basic changes to the transmitter and/or receiver parameters including modulation, symbol rates, frequency channels, symbol coding, and others that affect the throughput and performance of the communications channels when conditions change. (Ref. CCSDS 211.0-B-6, MTN-SYS-DESC-0001)

Traceability: MTN-OBJ-003, MTN-OBJ-004

MTN-REQ-035 Proximity Link 1-Way Doppler

Threshold Requirement: The MTN shall provide in situ 1-way Doppler tracking services to users with a precision of 0.5mm/s (1-sigma) at a 60 second count time.

Goal Requirement: The MTN shall provide in situ 1-way Doppler & Ranging services to users with a precision of 0.5mm/s (1-sigma) at a 60 second count time and ranging precision of 1 meter.

Rationale: Pseudo-range and one-way forward Doppler reference signals support navigation when two-way tracking is unavailable or impractical. These services support high-dynamics mission phases, reduce onboard complexity for users, and improve navigation continuity, autonomy, and overall mission resilience.

MTN-REQ-036 Proximity Link 2-Way Doppler

Threshold Requirement: The MTN shall provide for in situ 2-Way coherent Doppler tracking services to users with a precision of 0.5mm/s (1-sigma) at a 60 second count time with a latency of less than 10 seconds.

Goal Requirement: The MTN shall provide for in situ 2-way coherent Doppler & Ranging services to users with a precision of 0.5mm/s (1-sigma) at a 60 second count time and ranging precision of 1 meter with a latency of less than 10 seconds.

Rationale: Two-way coherent ranging and Doppler provide higher accuracy measurements

(relative to one-way measurements) needed for precise navigation and orbit determination.

These capabilities are essential for high-consequence operations and reduce mission risk by enabling stable, validated navigation solutions. Precision replicates current accuracy capability of existing systems.

MTN-REQ-037 Position, Navigation, and Timing (Service Reference Signals)

Threshold Requirement: The MTN shall make available a reference message containing MTN orbit and clock data to users with a signal-in-space error (SISE) contributions of root sum square

(RSS) position and velocity errors, respectively, of ≤100 meters and 5 cm/sec (3-sigma).

Goal Requirement: The MTN shall make available a reference message containing MTN orbit and clock data to users with a signal-in-space-errors (SISE) contributions of root sum square

(RSS) position and velocity errors, respectively, of ≤50 meters and 3 cm/sec (3- sigma).

Rationale: The MTN shall be capable of providing reference signals that can be used by all assets at any time to calculate their own position and time. SISE includes errors from: spacecraft on-board state knowledge (position, velocity and time), signal integrity and on-board path delays, predicted spacecraft states conveyed to users, and states and time representation. SISE does not include delays and phase noise introduced by the user system. The threshold value reflects what is achievable utilizing procurable USO clocks. The Goal value assumes use of atomic clock system. Guidance for the calculation of SISE is provided in Appendix C.

MTN-REQ-038 Advanced Proximity Link Protocol Standard

Threshold Requirement: MTN Advanced S-band or K/Ka-band proximity links shall comply with Section 4.2 LNSP-User Proximity Interfaces and Section 4.4 LNSP-User Contingency

Interfaces in the Lunanet interoperability Specification, Rev 5, and all Advanced Proximity

Links band shall implement a comparable interoperable (i.e. not proprietary) interface compliant with appropriate CCSDS protocol standards.

Rationale: The MTN will implement a non-proprietary standard for Proximity link protocol.

MTN-REQ-039 Open-Loop Recording

Threshold Requirement: The MTN shall provide open-loop recording for critical events (of 10 minutes in duration or less) at a selectable sampling rate ≤ 2 MHz with ≥ 8 bits per each component of a complex sample including recording at least 8 bits of AGC information and a 32-bit time tag at a rate ≥ 1 Hz.

Rationale: The MTN shall support the needed functionality currently available to legacy users during critical events (e.g. EDL, Mars Ascent, etc.) for all operational proximity bands.

Traceability: MTN-OBJ-003, MTN-OBJ-004

MTN-REQ-043 Service Provision to Surface Assets

Threshold Requirement: The MTN shall support communications and navigation with any surface asset in view of the MTN, when above 10 degrees elevation angle, measured from the surface asset to MTN.

Rationale: The MTN shall provide service to all surface users within view of the system. For the purposes link assessment, field of view below 10 degrees of elevation will not be supported.

Traceability: MTN-OBJ-001, MTN-OBJ-003

MTN-REQ-046 Legacy Proximity Link Spectrum

Threshold Requirement: The MTN Legacy Proximity Links shall operate at UHF frequency from

Table 3.

Label Link Direction Frequency

Proximity Forward Orbit-to-User: 435-450 MHz

Proximity Return User-to-Orbit 390-405 MHz

Table 3 Legacy Proximity Link Spectrum

Rationale: The proximity link frequency selection supports interoperability from different service providers for legacy and future user spacecraft, meet internationally coordinated spectrum, and where applicable, enables leveraging hardware and standards’ developments for the moon that may be used for Mars (e.g. LNIS, CLPS/CMPS, human class landers, rovers, habitats, payloads).

These values are aligned with the SFCG Recommendation, SFCG 22-1R4 and International

Table of Frequency Allocations for Mars. Note that these frequencies are currently SFCG recommendations only and do not guarantee allocation for Mars Proximity applications.

MTN-REQ-048 Advanced Proximity Link Spectrum

Threshold Requirement: The MTN Advanced Proximity links shall operate at a minimum of either S-band, Ku-band, or K/Ka-band frequency, from SFCG Recommended bands in Table 4 for User-to Orbit and Orbit to User links.

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